Optimization And Testing Of Digital - Analog Circuit And System Of EMC

Electron-Multiplying CCD (EMCCD) is a kind of imaging device that can amplify weak photoelectric signal inside the chip. In order to understand the characteristics better and master technologies of its application in astronomical imaging observation, an EMCCD camera system based on TC285is built in our laboratory with the support of the National Natural Science Foundation of China. The system consists of the following six large parts:a digital system based on FPGA, a level converting and driving module, a peripheral circuit of EMCCD, an analog signal processing chain, a data acquisition and transmission module based on Camera Link, and a man-machine interaction software system. In order to make the system perfect, we do a series of test, adjustment and optimization on various parts of the system.In this dissertation, we make a brief introduction for overall structure and design thinking of the EMCCD camera system, describe main hardware circuit and software system, and then focus on optimizing process and test results of circuit and system of the EMCCD camera. After analyzing timing characteristics of TC285and design requirements of the system, we optimize the digital control system in allusion to problems existing in test. Waveforms of timing generator in the digital control system and relevant test results of NiosⅡ controller and other auxiliary modules are also shown in this paper. According to electrical level requirement of EMCCD’s driving clock, we adjust the value of high and low level for each driving clock through actual test. At the same time, we find deficiency in the original design after testing clock driving circuit, do simulation and analysis with P Spice, and get the waveform which can meet the basic requirements after exchanging individual component. Based on these, installation and debugging of the hardware circuit and software system in EMCCD camera system are finished. In debugging on camera optical imaging, the parameters of the Analog Front End are adjusted to more appropriate value so as to obtain ideal images. Finally, we do some testing and analyze simply some characteristics of the camera.